The present invention relates generally to interconnection closures and, more particularly, to interconnection closures having a fiber management frame that optionally includes a connector platform to facilitate the interconnection of respective pairs of pre-connectorized optical fibers.
Fiber optic networks typically include interconnection closures at various connection points throughout the fiber optic network. Typically, these interconnection closures include splice closures, patch closures and the like. For example, splice closures commonly house the splices required to interconnect the optical fibers of one or more fiber optic feeder cables to respective ones of the optical fibers of a fiber optic drop cable. By housing the splices, a splice closure protects the spliced end portions of the optical fibers from environmental degradation, strain and other deleterious forces, thereby increasing the reliability and quality of the splices.
While fiber optic networks have traditionally served as the backbone or trunkline of communication networks to transmit signals over relatively long distances, fiber optic networks are gradually being extended closer to the end points of the communications networks. In this regard, fiber optic networks have been developed that deliver fiber-to-the-curb, fiber-to-the-home; fiber-to-the-business, fiber-to-the-desk and the like. In each of these different types of applications, a closure must be capable of splicing different types of cables to establish the proper interconnections. In this regard, the closure utilized in a fiber-to-the-home, fiber-to-the-business, or fiber-to-the-desk application is mounted upon a fiber optic feeder cable and one or more fiber optic drop cables to permit at least some of the optical fibers of the feeder cable to extend uninterrupted through the splice closure while connecting other optical fibers of the fiber optic feeder cable with optical fibers of a drop cable. In contrast, a closure that is utilized in a fiber-to-the-curb application is mounted upon not just a fiber optic feeder cable and one or more drop cables, but also an electrical feeder cable. In this application, the closure must facilitate the connection of one or more electrical conductors of the electrical feeder cable to corresponding electrical conductors of the drop cable, while permitting the remainder of the electrical conductors to extend uninterrupted through the closure. Additionally, the closure must facilitate the connection of one or more of the optical fibers of the fiber optic feeder cable with respective optical fibers of the drop cable while continuing to permit at least some of the optical fibers of the fiber optic feeder cable to extend uninterrupted through the closure.
In either type of closure, the optical fibers may be connected in different manners. In a splice closure, pairs of optical fibers are spliced together. In splice closures utilized in fiber-to-the-home and fiber-to-the-curb applications, for example, some of the optical fibers of the fiber optic feeder cable are spliced to respective optical fibers of the drop cable. In order to house the splice connections between respective pairs of optical fibers and to protect the splice connections, splice closures generally include one or more splice trays.
The splice connections established within a splice closure are high quality connections. Thus, the optical signals transmitted via respective pairs of optical fibers are not substantially attenuated or otherwise degraded by the splice connection. However, a technician must generally be quite skilled and well trained to accurately splice each respective pair of optical fibers within a splice closure. Even for a technician who is skilled and well trained, the process of splicing each respective pair of optical fibers may be a time consuming task if a relatively large number of splice connections must be established. Depending upon the type of splice connection, such as a mechanical splice, a fusion splice or the like, the technician may also be required to carry a substantial amount of equipment in order to splice the respective pairs of optical fibers.
Although not as common as splice closures, another type of closure has been developed to connect pre-connectorized optical fibers. This type of closure generally includes a number of connector sleeves, typically mounted within a connector bulkhead. By mounting fiber optic connectors upon the end portions of the optical fibers, pairs of optical fibers may be connected by inserting the fiber optic connectors mounted upon the end portions of the optical fibers into opposite ends of a connector sleeve. As will be apparent, a technician may readily connect a number of pairs of optical fibers and may easily reconfigure the connections by merely inserting the fiber optic connectors into different connector sleeves. However, this type of closure requires that fiber optic connectors be mounted upon the end portions of each of the optical fibers to be connected. The connectorization of the optical fibers not only requires the technician to provide the connector hardware, but may also require a substantial amount of time to mount the fiber optic connectors on the end portions of each optical fiber to be connected within the closure. Moreover, the resulting connection is generally of a lower quality than a splice connection with the optical signals being attenuated or otherwise degraded to a greater degree than if the optical fibers had been spliced together. In addition, this type closure typically only includes a small number of connector sleeves, such as six or eight connector sleeves, such that the number of pairs of optical fibers that may be connected in this manner is disadvantageously limited.
Different closures are generally provided to establish splice connections between respective pairs of optical fibers and to connect respective pairs of pre-connectorized optical fibers. Since different closures are provided depending upon the type of connection to be established, technicians must undergo additional training to be able to install each type of closure. Additionally, since different types of closures must be manufactured, additional costs are incurred to design and fabricate each different type of closure and to maintain a stock of each different type of closure in inventory. Accordingly, it would be desirable to provide a single closure capable of connecting respective pairs of optical fibers either by splicing or by inserting the connectorized end portions of the optical fibers into connector sleeves.
A fiber management frame and an interconnection closure that includes the fiber management frame are provided that may be configured to house splice connections or to connect pre-connectorized optical fibers by means of respective connector sleeves. In addition, the fiber management frame of the present invention is designed to facilitate the configuration of the closure and the routing of optical fibers therethrough.
According to one aspect of the present invention, a fiber management frame for an interconnection closure is provided that includes a frame, at least one optical fiber connection tray carried by the frame, and a connector platform including at least one connector sleeve mounted to the frame. According to one advantageous embodiment, the connector platform is detachably mounted to the frame such that the connector platform may be removed from the frame. By removing the connector platform from the frame, the fiber management frame may be converted from a fiber management frame adapted to connect respective pairs of pre-connectorized optical fibers by means of connector sleeves to a fiber management frame adapted to establish splice connections between respective pairs of optical fibers. Thus, a single fiber management frame may advantageously support each of these different types of connections.
According to one embodiment, the frame defines a plurality of compartments. At least one optical fiber connection tray is disposed within one compartment and the connector platform is disposed within another compartment. In one configuration, for example, the optical fiber connection tray is a splice tray that is disposed in a different compartment than the connector platform. In another configuration, the optical fiber connection tray is a coupler tray that is disposed in a different compartment than the connector platform. In this configuration, a splice tray may also be disposed within the same compartment as the connector platform. In either configuration, the splice tray serves to splice connectorized pigtails onto respective optical fibers, such as respective optical fibers of a fiber optic feeder cable. The connectorized pigtails may then be connected to other pre-connectorized fibers, such as the pre-connectorized optical fibers of a drop cable, by means of the connector sleeves.
The fiber management frame of the present invention is preferably readily accessible during configuration to facilitate the connection of respective pairs of the optical fibers. According to one aspect of the present invention, the fiber management frame includes a frame and a connector platform which, in turn, includes a shelf and a plurality of connector sleeves disposed upon the shelf. The connector platform is slidably connected to the frame to provide access to the connector platform. The connector platform is therefore adapted to move between a stowed position in which the connector platform is proximate the frame and an extended position in which the connector platform protrudes beyond the frame. Thus, the connector platform may be placed in the extended position to configure the closure and may thereafter be placed in a stowed position such that the closure may be closed and placed into service. The connector platform may be slidably connected to the frame in various manners. In one embodiment, however, the frame defines at least one track upon which the connector platform rides.
The fiber management frame is also preferably designed to facilitate routing of the optical fibers. In this regard, the fiber management frame of one aspect of the present invention includes a frame and a plurality of stacks of connector sleeves mounted upon the frame. Each stack of connector sleeves includes a plurality of connector sleeves disposed in a stacked relationship. Advantageously, each stack of connector sleeves is spaced from an adjacent stack to define a gap therebetween. Thus, optical fibers may be routed through the gap, if so desired. The stacks of connector sleeves may be disposed upon a shelf which, in turn, is mounted upon the frame. As described above in connection with other aspects of the present invention, the shelf may be slidably connected to the frame so as to move between stowed and extended positions and may be detachably mounted to the frame such that the shelf and the stacks of connector sleeves may be removed from the frame.
To further facilitate routing of the optical fibers, the fiber management frame of another aspect of the present invention includes a frame, first and second banks of connector sleeves mounted upon the frame in a spaced relationship, and at least one routing guide disposed between the first and second banks of connector sleeves for routing optical fiber to respective banks of connector sleeves. As described above in connection with other aspects of the present invention, the fiber management frame may further include a shelf mounted upon the frame with the first and second banks of connector sleeves being disposed upon the shelf. In one embodiment, the routing guides are spaced from the shelf. For example, the fiber management frame may include a panel that carries the routing guides and that is spaced from the shelf. Thus, the optical fibers engaged by the routing guides may be maintained above the shelf in order to reduce fiber congestion. Moreover, the fiber management frame may include a bias member for operably contacting the panel to prevent undesired movement, including both vibration of the panel and sliding motion of the shelf relative to the frame. As also described above in connection with other aspects of the present invention, the shelf may be slidably connected to the frame so as to move between stowed and extended positions and may be detachably mounted to the frame such that the shelf and the first and second banks of connector sleeves may be removed from the frame.
In addition to the various embodiments of the fiber management frame previously described, interconnection closures are provided according to another aspect of the present invention. The closure includes a housing defining an internal cavity and a plurality of ports opening into the internal cavity for receiving a plurality of cables. The closure also includes a fiber management frame, such as any one of the frame assemblies described hereinabove, disposed within the internal cavity of the housing. According to the present invention, a closure is therefore provided that may be alternately configured to connect respective pairs of pre-connectorized optical fibers by means of one or more connector sleeves or to establish splice connections between respective pairs of optical fibers. In those configurations adapted to connect pre-connectorized optical fibers, the closure of the present invention also facilitates the splicing of connectorized pigtails onto respective optical fibers, such as the optical fibers of a feeder cable in order to provide a convenient technique for connectorizing the optical fibers. In addition, the fiber management frame is preferably designed to facilitate access to the connector platform by permitting the connector platform to be slidably mounted upon the frame, thereby facilitating configuration of the connector platform. In addition, the fiber management frame is advantageously designed to appropriately route and guide optical fibers to respective connector sleeves, and thereby further facilitate configuration of the closure and prevent inadvertent damage to the optical fibers.